Hard disk drives (HDD), particularly those that are used in mobile computers, have to be designed to withstand the rough usage typically seen in the mobile environment. The shock robustness of such drives has improved primarily in the ability to withstand large shocks during the nonoperating mode. Typically, when not operating the slider assembly, which includes the read and write elements of the HDD, is “unloaded” by moving the slider onto a ramp near the outer diameter of the disk. In this way, in the event of shock the slider does not contact the disk, which could otherwise damage the slider and/or disk.
Before the drive is assembled, a slider orientation parameter referred to as “roll static attitude” (RSA) is set to zero on average, while a parameter referred to as “pitch static attitude” (PSA) is set slightly above zero on average (typically 100 min). What this means is that the slider has a slight pitch relative to the load beam of the suspension (non-zero PSA), i.e., the leading edge of the slider is slightly closer to the suspension than the trailing edge, whereas in the orthogonal dimension of roll the slider is parallel to the suspension (zero RSA, i.e., the radially outer edge of the slider is the same height as the radially inner edge).
With the above in mind, the present invention recognizes that during the load/unload process, it would be desirable to establish a non-zero RSA wherein the inner edge of the slider is closer to the load beam than the outer edge. With such a RSA, should the slider touch the disk during load/unload, it will be the outer edge of the slider that touches. Whatever damage to the disk that might occur consequently will happen almost just underneath the ramp, i.e., in a location beyond where data ordinarily is written. This in turn ensures that the risk of losing data due to slider-disk contact during load/unload is minimized or eliminated. The risk of flying over a damaged region of the disk is also reduced. Nonetheless, the present invention recognizes the desire to establish a zero RSA during normal operation for optimal performance.